From 2889c658b2fbc7ad4c5d541734fdc1d97b130753 Mon Sep 17 00:00:00 2001 From: Yuntao Wang Date: Thu, 20 Jan 2022 06:59:49 +0000 Subject: [PATCH] ftrace: Deal with error return code of the ftrace_process_locs() function The ftrace_process_locs() function may return -ENOMEM error code, which should be handled by the callers. Link: https://lkml.kernel.org/r/20220120065949.1813231-1-ytcoode@gmail.com Signed-off-by: Yuntao Wang Signed-off-by: Steven Rostedt (Google) --- kernel/trace/ftrace.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 6c5b12669e06..737e895e2aad 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -6864,11 +6864,16 @@ void ftrace_module_enable(struct module *mod) void ftrace_module_init(struct module *mod) { + int ret; + if (ftrace_disabled || !mod->num_ftrace_callsites) return; - ftrace_process_locs(mod, mod->ftrace_callsites, - mod->ftrace_callsites + mod->num_ftrace_callsites); + ret = ftrace_process_locs(mod, mod->ftrace_callsites, + mod->ftrace_callsites + mod->num_ftrace_callsites); + if (ret) + pr_warn("ftrace: failed to allocate entries for module '%s' functions\n", + mod->name); } static void save_ftrace_mod_rec(struct ftrace_mod_map *mod_map, @@ -7201,15 +7206,19 @@ void __init ftrace_init(void) pr_info("ftrace: allocating %ld entries in %ld pages\n", count, count / ENTRIES_PER_PAGE + 1); - last_ftrace_enabled = ftrace_enabled = 1; - ret = ftrace_process_locs(NULL, __start_mcount_loc, __stop_mcount_loc); + if (ret) { + pr_warn("ftrace: failed to allocate entries for functions\n"); + goto failed; + } pr_info("ftrace: allocated %ld pages with %ld groups\n", ftrace_number_of_pages, ftrace_number_of_groups); + last_ftrace_enabled = ftrace_enabled = 1; + set_ftrace_early_filters(); return; -- 2.39.5